(1) Field of the Invention
This invention relates to systems for the control of lead based paint on woodwork of homes, and more particularly to apparatus and method for covering woodwork painted with a lead based paint in homes and apartments.
(2) Prior Art
Lead poisoning poses a terrible environmental threat, particularly for young people. Levels of 25 micrograms of lead per deciliter of blood, if maintained in young children, can affect mental capacities and result in grave behavioral and physical problems.
About 3 million to 4 million American children, or about 1 out of every 6 under six years old, have lead poisoning. While only 7% of young children from medium income families are afflicted, about 25% of poor white children and an incredible 55% of those from low income minority families.
The United States Department of Health and Human Services warns that even moderate exposure to lead can be more pervasive and long lasting than previously thought. Government regulations have already phased out most leaded gasolines. Lead-based paints have been banned for most uses since 1977. However, a 1988 Public Health Service report revealed that 52%, or 42 million of the nation's households have layers of lead-based paint on their woodwork.
Lead is highly toxic even in minute quantities. Once it is ingested, lead enters the bloodstream, where it inhibits the production of hemoglobin which red blood cells need to carry oxygen. It also locks onto essential enzymes in the brain and central nervous system to inactivate them. Symptoms of lead poisoning include abdominal pains, muscular weakness and fatigue; severe exposure can cause nervous system disorders, high blood pressure and even death.
Small children have the greatest risk because their nervous systems and brains are still developing. Lead can be removed from humans by a process doctors call chelation, using drugs that bind to the metal in the bloodstream, and flush it out in the urine, if treatment is begun before too much damage is done.
However, medical treatment is no substitute for a safe environment. The Health and Human Services plan calls for (1) surveillance of children with elevated levels of lead in their blood; (2) elimination of leaded paint and contaminated dust in housing; (3) reduction of children's exposure to lead in food, air, soil and water; and (4) an increase in community programs for the prevention of childhood lead poisoning. Eliminating lead from all pre-1950 housing would save as much as $28 billion in medical expenses and other costs, but at an expense of about $10 billion to put this plan into effect over the next 10 years.
Eliminating the lead problem by painted encapsulants is a current hope of researchers at the University of Lowell in Lowell, Mass. Acrylic, polyester and epoxy are the planned materials which might be painted upon the lead paint surface where they will hopefully dissolve the paint and cross link with it onto the wood or plaster below. The goal appears to be to interlock the materials. Some of the tests done on the treated surfaces will include impact resistance. When you hit it, does it chip and produce lead dust? Abrasion and adhesion tests are also important, as will be aging tests to see how long the coating will last and what effect heat, light and household cleaners might have on it. The encapsulants will have to be developed, and of course, pass these aforementioned tests.
U.S. Pat. No. 4,391,072 to Moore entitled "Window Trim" describes a homeowner installable molded fiberglass for modifying the appearance of a window sill and jamb components, which is unsatisfactory for effective long term control of lead paint pollution.
U.S. Pat. No. 3,443,345 to Spencer shows an extruded rigid vinyl plastic cover for wood trim which is nailable to the wood through flapped grooves, which unfortunately creates openings through the covering, and also necessitates the disposition of grooves in the wood trim in which the cover groove must mate. The grooves can actually facilitate the release of the lead based paint.
U.S. Pat. No. 3,478,478 to Luebs shows an extruded, snap-on plastic cover for glass glazing or for particular trim components, to change their appearance, which does not however solve the lead paint problem on the woodwork, since this is merely a retainer for the glazing.
U.S. Pat. No. 3,130,455 to Borlenghi shows an extruded plastic door frame which covers bridging wood and forms a door case which permits new construction to be given a finished appearance with a plastic cover. This type of cover is susceptable to wear and damage long before any of the covering contemplated by the present invention.
U.S. Pat. No. 4,843,790 shows a casing trim of extruded thin siding vinyl including interlocking edges and nailed trim grooves for supporting the vinyl on the wood, again suffering from the same deficiencies of the other art.
The prior art trim covering, none of which is used for lead based paint control, is made by extruded or formed plastic, the use of which is only a short term solution, which plastic covering is subject to wear, cracking, sun or heat degradation and toxicity if combusted, and which shortcomings are all avoided by the present invention. Dust, particles and contaminants covered by Applicant's concept are safely and permanently excluded from the atmosphere, and from any possibility of being ingested by children.